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1
19
20 package edu.umd.cs.findbugs.ba.generic;
21
22 import java.util.Iterator  ;
23 import java.util.NoSuchElementException ;
24
25 import org.apache.bcel.classfile.Attribute;
26 import org.apache.bcel.classfile.FieldOrMethod;
27 import org.apache.bcel.classfile.Method;
28 import org.apache.bcel.classfile.Signature;
29 import org.apache.bcel.generic.ConstantPoolGen;
30 import org.apache.bcel.generic.InvokeInstruction;
31 import org.apache.bcel.generic.ObjectType;
32 import org.apache.bcel.generic.Type;
33
34 import edu.umd.cs.findbugs.annotations.CheckForNull;
35
36
44 public class GenericSignatureParser {
45 private class ParameterSignatureIterator implements Iterator <String > {
46 private int index = 1;
47
48 public boolean hasNext() {
49 return index < signature.length()
50 && signature.charAt(index) != ')';
51 }
52
53 public String next() {
54 if (!hasNext()) throw new NoSuchElementException ();
55 StringBuffer result = new StringBuffer ();
56 boolean done;
57 do {
58 done = true;
59 int ch = signature.charAt(index);
60 switch (ch) {
61 case 'B':
62 case 'C':
63 case 'D':
64 case 'F':
65 case 'I':
66 case 'J':
67 case 'S':
68 case 'Z':
69 case '*': result.append(signature.charAt(index));
71 ++index;
72 break;
73
74 case 'L':
75 case 'T':
76 String tmp = "";
77 int startsemi = index;
78 int semi = -1;
79 do {
82 semi = signature.indexOf(';', startsemi + 1);
83 if (semi < 0)
84 throw new IllegalStateException ("Invalid method signature: " + signature);
85 tmp = signature.substring(index, semi + 1);
86 startsemi = semi;
87 } while(tmp.split("<").length != tmp.split(">").length);
88 result.append(tmp);
89 index = semi + 1;
90 break;
91
92 case '[':
93 case '+':
94 case '-':
95 result.append(signature.charAt(index));
96 ++index;
97 done = false;
98 break;
99
100 case 'V':
101 default:
102 throw new IllegalStateException ("Invalid method signature: " + signature);
103 }
104 } while (!done);
105
106 return result.toString();
107 }
108
109 public void remove() {
110 throw new UnsupportedOperationException ();
111 }
112 }
113
114 private final String signature;
115
116
122 public GenericSignatureParser(String signature) {
123 if (signature.indexOf('(') < 0 || signature.indexOf(':') >= 0)
125 throw new IllegalArgumentException ("Bad method signature: " + signature);
126 if (!signature.startsWith("("))
127 this.signature = signature.substring( signature.indexOf("(") );
128 else
129 this.signature = signature;
130 }
131
132
137 public Iterator <String > parameterSignatureIterator() {
138 return new ParameterSignatureIterator();
139 }
140
141
146 public String getReturnTypeSignature() {
147 int endOfParams = signature.lastIndexOf(')');
148 if (endOfParams < 0)
149 throw new IllegalArgumentException ("Bad method signature: " + signature);
150 return signature.substring(endOfParams + 1);
151 }
152
153
158 public int getNumParameters() {
159 int count = 0;
160 for (Iterator <String > i = parameterSignatureIterator(); i.hasNext();) {
161 i.next();
162 ++count;
163 }
164 return count;
165 }
166
167
174 public static int getNumParametersForInvocation(InvokeInstruction inv, ConstantPoolGen cpg) {
175 GenericSignatureParser sigParser = new GenericSignatureParser(inv.getSignature(cpg));
176 return sigParser.getNumParameters();
177 }
178
179
185 public static @CheckForNull Iterator <String > getGenericSignatureIterator(Method target) {
186 try {
187 GenericSignatureParser parser = null;
188 String genericSignature = null;
189 for (Attribute a : target.getAttributes()) {
190 if (a instanceof Signature) {
191
192 Signature sig = (Signature) a;
193 if ( genericSignature != null) {
194 if (!genericSignature.equals(sig.getSignature()) ) {
195 if (false) {
196 System.out.println("Inconsistent signatures: " );
197 System.out.println(genericSignature);
198 System.out.println(sig.getSignature());
199 }
200 return null; }
202 continue;
203 }
204
205 genericSignature = sig.getSignature();
206 if (compareSignatures(target.getSignature(), genericSignature))
207 parser = new GenericSignatureParser( genericSignature );
208 }
209 }
210 Iterator <String > iter = parser == null ? null :
211 parser.parameterSignatureIterator();
212 return iter;
213 } catch (RuntimeException e) {} return null;
215 }
216
217
221 public static boolean compareSignatures(
222 String plainSignature, String genericSignature) {
223 GenericSignatureParser plainParser =
224 new GenericSignatureParser( plainSignature );
225 GenericSignatureParser genericParser =
226 new GenericSignatureParser( genericSignature );
227
228 if (plainParser.getNumParameters() != genericParser.getNumParameters())
229 return false;
230
231 return true;
232 }
233
234
235 public static void main(String [] args) {
236 if (args.length != 1) {
237 System.err.println("Usage: " + GenericSignatureParser.class.getName() + " '<method signature>'");
238 System.exit(1);
239 }
240 GenericSignatureParser parser = new GenericSignatureParser(args[0]);
241 for (Iterator <String > i = parser.parameterSignatureIterator(); i.hasNext();){
242 String s = i.next();
243 System.out.println(s);
244 Type t = GenericUtilities.getType(s);
245 System.out.println("-~- " + t);
246 if (t instanceof ObjectType)
247 System.out.println("-~- " + ( (ObjectType) t).toString());
248 System.out.println("-~- " + t.getClass());
249 }
250 System.out.println(parser.getNumParameters() + " parameter(s)");
251
252
253 }
254 }
255
256 |
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